Adds `--base-path to solc when compiling in --standard-json mode for resolving relative paths.

solc/CommandLineInterface.cpp

@@ -107,6 +107,7 @@ std::ostream& serr(bool _used = true)
 static string const g_stdinFileNameStr = "<stdin>";
 static string const g_strAbi = "abi";
 static string const g_strAllowPaths = "allow-paths";
+static string const g_strBasePath = "base-path";
 static string const g_strAsm = "asm";
 static string const g_strAsmJson = "asm-json";
 static string const g_strAssemble = "assemble";
@@ -181,6 +182,7 @@ static string const g_strOldReporter = "old-reporter";
 static string const g_argAbi = g_strAbi;
 static string const g_argPrettyJson = g_strPrettyJson;
 static string const g_argAllowPaths = g_strAllowPaths;
+static string const g_argBasePath = g_strBasePath;
 static string const g_argAsm = g_strAsm;
 static string const g_argAsmJson = g_strAsmJson;
 static string const g_argAssemble = g_strAssemble;
@@ -830,6 +832,11 @@ Allowed options)").c_str(),
 			po::value<string>()->value_name("path(s)"),
 			"Allow a given path for imports. A list of paths can be supplied by separating them with a comma."
 		)
+		(
+			g_argBasePath.c_str(),
+			po::value<string>()->value_name("path"),
+			"Use the given path as the root of the source tree instead of the root of the filesystem."
+		)
 		(g_argColor.c_str(), "Force colored output.")
 		(g_argNoColor.c_str(), "Explicitly disable colored output, disabling terminal auto-detection.")
 		(g_argOldReporter.c_str(), "Enables old diagnostics reporter.")
@@ -965,7 +972,8 @@ bool CommandLineInterface::processInput()
 			string validPath = _path;
 			if (validPath.find("file://") == 0)
 				validPath.erase(0, 7);
-			auto path = boost::filesystem::path(validPath);
+
+			auto const path = m_basePath / validPath;
 			auto canonicalPath = boost::filesystem::weakly_canonical(path);
 			bool isAllowed = false;
 			for (auto const& allowedDir: m_allowedDirectories)
@@ -1003,6 +1011,19 @@ bool CommandLineInterface::processInput()
 		}
 	};
 
+	if (m_args.count(g_argBasePath))
+	{
+		boost::filesystem::path const fspath{m_args[g_argBasePath].as<string>()};
+		if (!boost::filesystem::is_directory(fspath))
+		{
+			serr() << "Base path must be a directory: \"" << fspath << "\"\n";
+			return false;
+		}
+		m_basePath = fspath;
+		if (!contains(m_allowedDirectories, fspath))
+			m_allowedDirectories.push_back(fspath);
+	}
+
 	if (m_args.count(g_argAllowPaths))
 	{
 		vector<string> paths;

solc/CommandLineInterface.h

@@ -117,6 +117,8 @@ private:
 	std::vector<frontend::CompilerStack::Remapping> m_remappings;
 	/// list of allowed directories to read files from
 	std::vector<boost::filesystem::path> m_allowedDirectories;
+	/// Base path, used for resolving relative paths in imports.
+	boost::filesystem::path m_basePath;
 	/// map of library names to addresses
 	std::map<std::string, util::h160> m_libraries;
 	/// Solidity compiler stack